The aim of this study was to validate the SENIAM recommendations for surface electromyography placement(sEMG) over rectus femoris(RF) muscle in healthy children and in children with cerebral palsy(CP) during gait analysis and compare placement using these guidelines to using ultrasonography. Methods & Results:. The study included 10 healthy children volunteers and 10 CP children volunteers, aged 8–12. All the CP children had spastic diplegia, were GMFCS levels I–II and had not previously undergone surgery. RF electrodes were placed following SENIAM recommendations. RF was then identified by ultrasound. The distance between the lateral edge of RF and the position of the sEMG electrode as per SENIAM guidelines and the width of RF was measured, to the nearest millimetre. We considered ‘ideal electrode’ position to be at halfway between the edges of RF (i.e. 50%). The mean percentage difference in distance from the ‘ideal electrode’ position as measured by ultrasound to electrode placement following SEMIAN guidelines was 2.7% in the healthy children group compared with 19.5% in the CP group. By performing unpaired t tests we showed that there was no significant difference between the mean electrode position using SEMIAN guidelines and ‘ideal electrode’ position in the healthy children (p=0.0531), however the mean electrode position using SEMIAN guidelines in the CP patients was significantly different from the ‘ideal electrode’ position (p=0.0001). Conclusion:. SENIAM recommendations for sEMG electrode placement over RF muscle were validated in 10 healthy children. We showed that ultrasonography improved the accuracy of sEMG electrode placement in children with CP, who can exhibit anatomical variation due to their condition. Accurate electrode placement will ensure that a more accurate signal is recorded which may have a direct clinical bearing on the decision to proceed with surgical intervention. Level of evidence: II

We report the results of Vulpius transverse gastrocsoleus recession for equinus gait in 26 children with cerebral palsy (CP), using the Gait Profile Score (GPS), Gait Variable Scores (GVS) and movement analysis profile. All children had an equinus deformity on physical examination and equinus gait on three-dimensional gait analysis prior to surgery. The pre-operative and post-operative GPS and GVS were statistically analysed. There were 20 boys and 6 girls in the study cohort with a mean age at surgery of 9.2 years (5.1 to 17.7) and 11.5 years (7.3 to 20.8) at follow-up. Of the 26 children, 14 had spastic diplegia and 12 spastic hemiplegia. Gait function improved for the cohort, confirmed by a decrease in mean GPS from 13.4° pre-operatively to 9.0° final review (p < 0.001). The change was 2.8 times the minimal clinically important difference (MCID). Thus the improvements in gait were both clinically and statistically significant. The transverse gastrocsoleus recession described by Vulpius is an effective procedure for equinus gait in selected children with CP, when there is a fixed contracture of the gastrocnemius and soleus muscles.

Cite this article: Bone Joint J 2015;97-B:564–71.